MOSCOW
— The demonstrators camped out this week on Kiev's Independence Square are far fewer than the throngs of 2004's Orange Revolution – the two-week-long mass protest that overturned a rigged election, allowed the movement's leader, Viktor Yushchenko, to become president, and seemed to secure a democratic future for Ukraine.

This time, the tent city on Kiev's main street is festooned with the blue banners of the Orange Revolution's opponents, and the nightly rallies are filled with ringing denunciations of Mr. Yushchenko's "undemocratic" and "power-grubbing" behavior.

Despite the relative paucity of demonstrators compared with 2004, experts say this is Ukraine's most serious crisis yet. Even though the general population remains largely uninvolved, the threat of a national breakup looks increasingly real.

"This is a fight between the leaders and their most active supporters, but it has already gone too far," says Oleksandr Shushko, an expert with the independent Institute for Euro-Atlantic Integration in Kiev. "It's becoming clear that our current constitutional model is not workable at all."

Opinion polls suggest that two years of constitutional gridlock have left most Ukrainians exhausted and disillusioned with political leaders of every stripe who never seem to do anything but squabble. Yushchenko's early-April decree ordering the Blue-dominated parliament, the Supreme Rada, to disband and face new elections on May 27, is opposed by nearly 60 percent of Ukrainians, according to a recent survey by the independent Sofia Social Studies Center in Kiev. Yet that poll does not appear to reflect support for the Blue forces, led by Prime Minister Viktor Yanukovich, who have hunkered down in the Rada and refused to obey the president. Several polls released last week suggest that Mr. Yanukovich's Party of Regions, based in the Russified east, enjoys the backing of no more than 35 percent of voters – the same percentage with which it won in parliamentary polls a year ago.

Before the crisis erupted in early April, Yanukovich had been fortifying his parliamentary majority by inducing deputies from the two pro-democracy Orange parties to cross the floor. Yanukovich had bragged that by summer his coalition would have 300 members in the 450-seat Rada – the magic number required to override presidential vetoes. Yushchenko reacted to his depleting ranks on April 2, when he accused the Blue parties of bribing Orange lawmakers, dispersed the Rada, and ordered fresh elections.

"The key issue here is that the only democratic way of getting out of this deep crisis ... lies in new elections," Yushchenko said on Wednesday in an interview with Radio Free Europe.

The Constitutional Court has agreed to begin hearings on April 17, but that is also the legal deadline for all parties to register for the snap elections, meaning the immediate crisis is likely to go unresolved.

"For us, there is no way out but through the cancellation of the president's unconstitutional decree," says Vasyl Khara, head of the Party of Regions caucus in the embattled Rada. Otherwise, he says, the Blue coalition may refuse to take part in the May 27 polls.

In the past week, five judges of the 18-member Constitutional Court abruptly resigned, citing unspecified "threats" and "political pressure." Three more judges were checked into the hospital over the weekend with unspecified medical complaints. Experts say the court can continue to operate with a 10-member quorum, but that the episode raises worries that Ukraine's fledgling institutions may not be able to contain the escalating dispute.

"It will be very unfortunate if, after all this turmoil, we don't develop better checks and balances in our system," says Vira Nanivska, president of the official National Academy for Public Administration in Kiev.

At a Kiev rally last week, Yanukovich said that he would vacate the Rada only if Yushchenko agrees to face the voters, too. "If we hold early elections, they must be parliamentary and presidential, and held within the framework of current legislation," he said. That solution might also appeal to the ambitious Yulia Tymoshenko, who leads the Orange-hued All-Ukrainian Union Fatherland party and who has made little secret of her impatience with Yushchenko, her cautious ex-ally.

For his part, Yushchenko said in a speech last Thursday that he's not wedded to the May 27 date for new parliamentary polls and that he would allow deputies to reconvene in the Rada to decide on a fresh date.

But polls suggest that a new election may only reproduce the current stalemate. Experts warn that failure to find a compromise will lead to a permanent crisis and, in the worst case, even Ukraine's breakup. Deep divisions between the country's heavily industrialized, Russified east and its agricultural, Ukrainian-speaking, and pro-European west, seem certain to continue generating conflict over flash point issues like NATO membership, economic cooperation with Russia, and official status for the Russian language. Until Ukraine's Constitutional Court renders a decision or one of the antagonists blinks, the country's worst political crisis since the collapse of the USSR is likely to go rolling on.

"Our political competition is not between right and left, but between east and west, and this is a potential disaster," says Ms. Nanivska.